Goth-worthy circles are usually genetic, meaning they aren't your fault. Except, of course, when they are. Jessica Wu, an assistant clinical professor of dermatology at the University of Southern California's Keck School of Medicine in Los Angeles, reveals the four bad habits that can make shadows worse.

It's easy to forget that many active ingredients—found in anti-aging creams, acne treatments, peels, and more—are surprisingly fragile. It's only a matter of time until oxygen and heat render them useless. We asked Amy Wechsler, assistant clinical professor of dermatology at SUNY Downstate Medical Center in Brooklyn, to guide us through the various expiration dates.

Crow's-feet and crinkled skin don't stand a chance against Fredric Brandt. The world's largest single consumer of Botox and Restylane, Brandt has offices in New York City and Coral Gables, Florida, and serves as skin guru to Madonna and Emmy Rossum.